The present invention relates to a fuel cap, and particularly to a fuel cap for closing a vehicle fuel tank filler neck. More particularly, the present invention relates to an electrically conductive fuel cap.
Occasionally, vehicle occupants or service station attendants will xe2x80x9ccarryxe2x80x9d a static electricity charge having an electrical potential that is higher than the vehicle itself. A fuel cap in accordance with the present invention is configured to xe2x80x9cgroundxe2x80x9d a person touching the fuel cap prior to removal of the fuel cap from the filler neck so as to dissipate to ground, in a controlled manner, any electrostatic charge or potential on the person at the outset of a vehicle refueling cycle and before fuel vapor is allowed to vent through the mouth of the filler neck.
In a preferred embodiment, the fuel cap includes a handle, a fuel port closure for engaging a fuel receiving assembly, an electrically conductive retainer on the fuel cap and a seal. The electrically conductive retainer maintains an electrically conductive contact to the fuel receiving assembly while the seal prevents the escape of fuel vapors through the fuel receiving assembly. The seal is maintained until substantially achieving a common electrical potential between the cap and the fuel receiving assembly by way of the electrically conductive retainer.
The invention also includes a method of establishing a common electrical potential and preventing escape of fuel vapors from a fuel port of a fuel receiving assembly prior to establishing the common electrical potential. The method employs a fuel receiving assembly which defines a fuel port, a fuel cap which is engageable with and covers the fuel port. The cap includes an electrically conductive retainer, a handle, a fuel port closure and a seal. The seal is maintained between the cap and the fuel receiving assembly. When the cap is engaged with the fuel receiving assembly. A common electrically conductive path is established between the electrically conductive retainer and an electrically conductive portion of the fuel receiving assembly. The electrically conductive path is maintained between the retainer and the fuel receiving assembly until the common electrical potential is achieved. The seal is maintained and only disengaged after substantially achieving the common electrical potential.
Additional features and advantages of the invention will become apparent to those skilled in the art upon a consideration of the following detailed description of a preferred embodiment exemplifying the best mode of carrying out the invention as presently perceived.